New Device Turns Waste Heat into Electricity

[Rog]

Physicists have developed a way to turn heat into sound and then electricity, suggesting a new way to effectively recycle waste energy. “We are converting waste heat to electricity in an efficient, simple way by using sound,” said the scientist who led the effort, Orest Symko of the University of Utah.

New Device Turns Waste Heat into Electricity | LiveScience

[forfismum]

Not knocking that idea Rog,but we have umpteen ideas and working devices to save energy but nobody seems to use them.Even the simple idea of clicking off a light switch is beyond the ken of most folks.Devices such as heat pumps lie rusting for want of attention and yet every week it seems that a fortune is spent on "new" ways of doing this and that.Why do we have "waste heat" in the first place?

[prashamk]

Quite true forfismum... First human tendency, their consumption patterns need to be changed. Effeciency shall follow automatically.

One way is to hike prices of energy like anything. (a bit higher than what it is today)

[LMagic007]

Originally Posted by forfismum

Not knocking that idea Rog,but we have umpteen ideas and working devices to save energy but nobody seems to use them.Even the simple idea of clicking off a light switch is beyond the ken of most folks.Devices such as heat pumps lie rusting for want of attention and yet every week it seems that a fortune is spent on "new" ways of doing this and that.Why do we have "waste heat" in the first place?

That's a notable point, however the pragmatic reality is that heat is wasted not just from new technology, but also from existing technology and if there are efficient and cost effective ways of tapping into that waste heat to produce electricity, then it could be said to be a worthy pursuit. Take for one example motor vehicle engines. Waste heat is just a reality, so if it can be dealt with more effectively, I see that as a good thing. Perhaps a device like this could also help reduce waste heat in future devices, by making them more energy efficient and reducing overall power consumption. That may help answer the question "Why do we have "waste heat" in the first place?" because a power saving device like this could potentially help avoid wasting heat. Of course we should do the commonsense things to save energy, whilst also developing new ideas.

Well done for the post Rog, we very much need new ideas, besides old ones.

[Besoeker]

Originally Posted by forfismum

Not knocking that idea Rog,but we have umpteen ideas and working devices to save energy but nobody seems to use them.Even the simple idea of clicking off a light switch is beyond the ken of most folks.Devices such as heat pumps lie rusting for want of attention and yet every week it seems that a fortune is spent on "new" ways of doing this and that.Why do we have "waste heat" in the first place?

I think switching off unused devices is a simple, effective and practical step that can be used with immediate effect and requires no new technology.

[Besoeker]

Originally Posted by forfismum

Why do we have "waste heat" in the first place?

Any system that controls or converts energy has losses. That loss is mostly in the form of heat.
As an example, most of the energy used to power a light bulb is dissipated in heat loss.
As I'm sure you already knew...

[forfismum]

Originally Posted by Besoeker

Any system that controls or converts energy has losses. That loss is mostly in the form of heat.
As an example, most of the energy used to power a light bulb is dissipated in heat loss.
As I'm sure you already knew...

aha you caught me out Besoeker Can I nit-pick like some our pals in this winderful forum and say that heat loss and waste heat are not the same thing?

[Besoeker]

Originally Posted by forfismum

aha you caught me out Besoeker Can I nit-pick like some our pals in this winderful forum and say that heat loss and waste heat are not the same thing?

Of course you can nit pick.
Looking at the humble light bulb again, if you put 100W into it 95W or more is converted to heat. Unless you make use of that heat loss it is wasted. Doesn't that make it waste heat?

[forfismum]

Aha aha aha ahaaaaaaaaaaaaaa but why is it waste heat ? Our lamp is part of the energy make up of our home most of the time.Only a daft haporth like elmagico would go chasing after a car to capture the heat loss from its engine but think of where we would find heat loss that we can prevent become waste heat.Interesting that in past times cattle were housed under the domestic part of farm buildings thus turning the respiratory heat loss from the moos into useful heat.No "waste heat " in yer House of Denmark young Yorick

[Besoeker]

Originally Posted by forfismum

Aha aha aha ahaaaaaaaaaaaaaa but why is it waste heat ? Our lamp is part of the energy make up of our home most of the time.

Unless your house is so well insulated with three foot thick walls and a thatched roof that you never need heating. If you don't need the heat........

Originally Posted by forfismum

Interesting that in past times cattle were housed under the domestic part of farm buildings thus turning the respiratory heat loss from the moos into useful heat.No "waste heat " in yer House of Denmark young Yorick :-"

Yes, respitory and body heat. But hamlets have evolved and not so many residences have cattle within spitting distance.

On a slightly more serious note, I have been concerned with energy efficiency for most of my working life. This is in the context of industrial process systems. Energy efficiency is something industry took seriously a long time before the commercial and domestic sectors. As a result, industrial equipment using significant amounts of energy, has become much more efficient both inherrently and in the means of control.

As an example, electric motors are typically 95% efficient. At best, any improvement over that is tinkering at the margins. The way to save energy is to switch it off when it isn't needed. Which was the point you made in the first place.